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MikroTik App
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Posts: 122
Joined: Thu Jul 29, 2010 9:33 pm


Thu Jul 19, 2012 3:32 pm

I have a MikroTik RB450G that I am trying to connect to some Cisco switches.

The problem I'm running into is that when I connect the MT the Cisco complains of:

*Apr 11 15:13:41.822: %SPANTREE-2-PVSTSIM_FAIL: Blocking designated port Gi1/0/21: Inconsitent superior PVST BPDU received on VLAN 300, claiming root 32768:0022.904b.f400

and shuts down the port between the Cisco and the RouterBoard.

What do I need to do to make the MikroTik NOT have the superior PVST value? I don't even have PVST, MST, or STP configured on the MikroTik.

The network setup is:

Cisco<--->Cisco<--->Cisco<--RADWIN Microwave Hop-->MikroTik--->Some Wireless Equipment

The bizarre part is if I take the MikroTik and connect it directly to the last Cisco and plug my laptop in it works fine. If I plug the MikroTik into the RADWin I seem to get port shut downs on the Cisco side.

The MikroTik setup is such that:
Ports 0,1,2 are Trunked with VLANs 50,100,200,300 and Ports 3,4 are Access Ports for VLAN 300.
With switch-all-ports=no and no master ports set. Ports 0,1,2 are in a bridge group and ports 3 and 4 are in a bridge group.
Posts: 40
Joined: Tue Dec 07, 2010 1:57 am
Location: Bratislava, Slovakia

Re: VLAN Root

Thu Jul 19, 2012 5:44 pm

Can you post MK 450G config?
Which cisco has bridge ID 0022.904b.f400?

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